BCM1250/BCM1125/BCM1125H
User Manual
10/21/02
B r o a d c o m C o r p o r a t i o n
Page
100
Section 5: L2 Cache
Document
1250_1125-UM100CB-R
R
EGISTERS
The L2 tag registers are UNPREDICTABLE until the first event that causes them to be written. The
performance of reads to the registers will be low, while a read is in progress hardware will delay accesses to
the L2 Cache registers and any registers in the SCD.
Table 56: Level 2 Cache Tag Register
Bits
l2_read_tag -
00_1004_0018
l2_ecc_tag -
00_1004_0038
READ ONLY
4:0
0
14:5
Index
15
Tag bit 39 (holds index bit 15 in a 256KB or 512KB cache and is a tag bit in
a 128KB cache)
16
Tag bit 40 (holds index bit 16 in a 512KB cache and is a tag bit in a 256KB
or 128KB cache)
38:17
Tag bits
39
0
45:40
Tag ECC (raw).
47:46
Way
48
Dirty
49
Valid
59:50
Data ECC (raw)
63:60
Reserved
Table 57: Level 2 Cache Settings Register
Bits
l2_misc_value -
00_1004_0058
READ ONLY
Sytem Revision PERIPH_REV3 and later only
3:0
Cache quadrant information [t,b,r,l] (Broadcom Use Only)
7:4
l2_cache_disable
register value
8
Reads back enable for use of low priority memory blocker from value written
as bit [10] in the
l2_misc_config
register address
9
Reads back disable of ECC cleanup from value written as bit [11] in the
l2_misc_config
register address
13:12
Reads back
l2_way_enable
register
63:14
Reserved